Thermodynamic System: Closed vs Controlled Volumes

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A closed system cannot be classified as a controlled volume system because controlled volumes are specifically used to analyze open systems with material and energy flow. In a closed system, no materials enter or exit, eliminating the need for a control volume definition. Control volumes are typically associated with devices like valves that regulate flow. The discussion highlights that while closed systems can be referred to as controlled mass systems, the conventional terminology distinguishes between controlled volumes and closed systems. Understanding these distinctions is crucial for accurate thermodynamic analysis.
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Why a closed system can't be called as a Controlled Volume system?
 
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"Controlled volume" is not all closed systems.
 
Well, a control volume is a mathematical tool we set up on an open system in order to account for material flow streams (and energy flow streams, too) entering and exiting said system. Normally, we decide how to define a control volume for an open system. In a closed system, there are no materials entering or leaving the system, and the system usually has its boundaries well defined, so there's no need for us to define a control volume.
 
I agree with mexcheme.
Control volume means a device is used to control the volume; commonly valve is used.
Closed system is used usually in refrigerant system.
 
Well.Thanq MexchemE i got it.
Someone mentioned that we can call a Closed system as a controlled mass system and an Open system as a Controlled volume one...

Here the Truth is we are using a controlled volume in an open system and that's the point... So we can't simply call it a Controlled Volume system..
 
holdmenow said:
I agree with mexcheme.
Control volume means a device is used to control the volume; commonly valve is used.
Closed system is used usually in refrigerant system.
This is not the conventional terminology that is used.
 
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